As is well known, a microscope is an optical instrument used to view, examine and study very small objects. There are many different types of microscopes, each best suited to particular applications. These include compound microscopes, stereomicroscopes, confocal microscopes, inverted microscopes, and laser microscopes, to name but a few.
The present invention relates generally to compound microscopes and to those microscopes that are equipped with a sample stage capable of being controlled by a stage drive mechanism.
Microscopes have long used stages for the positioning of samples within the optical path. Such stages usually have a flat planar surface upon which an object or object holder rests. Such objects are specimens or samples for microscopic examination. An object, i.e. a specimen or sample, can be manipulated by moving the stage, or a portion thereof, in an x, y and z axes
Often, the focusing mechanism of a microscope functions by adjusting the stage height in the z axis, which is usually in line with or parallel to a light path from a light path into an objective lens of a microscope. By changing the sample height, the microscopist can focus upon the object and can focus and observe different depths within the z-axis of the sample. The focusing mechanism usually involves at least one rack and a matching pinion construction for adjusting the height of, i.e. raising and lowering, the stage. The rack is usually attached to the stage and the pinion is directly or indirectly rotatably attached to the frame so that rotation of the pinion raises and lowers the stage along the rack. At least one focusing knob is in turn secured to the pinion so that rotation of the focusing knob in turn rotates the pinion. In better microscopes, focusing knobs are attached on both the left and right of the microscope to permit easy left and right hand operation of a focusing knob.
The x and y axes are generally perpendicular to the z axis and to each other. Conventionally, the x axis is considered to be left and right relative to an operating microscopist during normal operation and the y axis is considered to be forward and backward relative to the operating microscopist during normal operation. The z axis is usually up and down relative to the earth during normal; operation. It is to be understood that the directions described above are relative directions to each other and when the microscope is not in operation may not maintain the above described relationship to a microscopist or the earth.
In order to adjust the x or the y position of the object, the user must have available a control mechanism capable of performing this movement. Typically such mechanisms are simple manual slides or involve pinion and rack or cable and pulley mechanisms or combinations thereof.
Due to the variety of microscopists using these instruments, both left & right-handed stages are desirable. The location of the stage control mechanism is preferably on the side of the stage matching the user's predominant hand of use. Further complicating the problem, a laboratory may have a left-handed and a right-handed user sharing a single microscope.
A further very significant problem with existing microscopes is that control mechanisms, for adjusting x-y position of an object, by moving the stage or portions thereof, i.e. x-y control, have been placed inconveniently causing difficult operation. Such known x-y control mechanisms have, for example, been placed at the rear of the stage or behind a focusing knob and have thus not been conveniently placed for single hand operation of both the x-y control and focusing knob with minimal, e.g. less than a five centimeter, hand movement. Further, such known x-y controls have not even been conveniently placed for dual hand operation of both the x-y control and focusing knob without requiring inconvenient postural positions by the microscopist. Such x-y controls have thus been ergonomically unsatisfactory.